We still have two months to go, so anything can happen, but at the moment “Before I Go To Sleep” looks like this year’s grand-prize winner for Most Befuddling Narrative Structure. Nicole Kidman is Christine Lucas, a wife and frightened recluse whose memory is only marginally better than that of Leonard, the amnesiac played by Guy Pearce in “Memento.” He can’t form new memories at all. She retains what happens during the course of each day, but her mind erases everything overnight. As a result of her condition, which was caused by some sort of terrible trauma, her husband, Ben (Colin Firth in full melancholy mode),...